1. Field of the Invention
The present invention relates to a nebulizer for atomizing a liquid, for instance, for nebulizining a medical liquid against a throat.
2. Description of the Prior Art
Conventionally, there are various nebulizers of different types. FIGS. 1a to 1c are cross-sectional views showing the essential portion of the prior-art nebulizers.
The construction of the nebulizer shown in FIG. 1a is such that a compressed air introduction pipe 101 is provided so as to pass through a side wall of a housing 100, and an end of a suction pipe 104 whose base end is put in a liquid reservoir 103 is positioned near a nozzle 102 formed at an end of the compressed air introduction pipe 101. Further, although being the same as in FIG. 1a, the construction of the nebulizer shown in FIG. 1b is such that a baffle 106 is disposed near both ends of the nozzle 102 and the liquid suction pipe 104. Further, in the nebulizer shown in FIG. 1c, a single or plural small-diameter liquid suction passages (pipes) 108 are formed at the outer circumference of a compressed air introduction pipe 107 integral therewith.
In use, a pressure pump connected to the compressed air introduction pipe is driven to obtain a jet stream through the nozzle, in every nebulizer. In this operation, a vacuum generated near the nozzle sucks a liquid in the liquid suction pipe (or passages) toward the nozzle on the basis of vacuum eject action. The liquid sucked upward is mixed with the jet stream, collides against the baffle, and is atomized before discharged outside through an atomized liquid discharge part of the housing.
In the prior-art nebulizers as described above, since the liquid suction pipe or passages are small in diameter, there exist drawbacks in that the liquid suction pipe is subjected to clogging due to crystals of medical liquid or coarse dirt particles.
In addition, in the prior-art nebulizers, since the liquid suction pipe is formed integral with the housing or the liquid suction passage is formed integral with the compressed air introduction pipe, it is very difficult to clean the clogged liquid suction pipe or passages, thus obstructing a safe nebulization. Further, in the case of a nebulizer in which the liquid suction passages are formed integral with the compressed air introduction pipe, there exist other problems such that the forming process is complicated, thus resulting in higher manufacturing cost and complicated repair work in case of nebulizer trouble.